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Heavy metals cause alarming levels of environmental and health problems and among them Cadmium has become a threat to organisms and natural resources like soil and water alike. It accumulates in living systems thereby causing oxidative stress. Efforts are made for bioremediation of heavy metals by employing biosorption, which is a well-known economic method for removal and in the current study Selaginella bryopteris was used as biosorbent. The biosorption capacity was optimized by its physicochemical parameters such as pH, dosage, contact time, and temperature. Cadmium-induced Reactive Oxygen Species levels and the antioxidant potential of S. bryopteris in ameliorating them were studied in Drosophila melanogaster. Water-quality analysis was performed using Chemical Oxygen Demand(COD) and Biological Oxygen Demand (BOD) and effect of S.bryopteris on these parameters were also analyzed. Further the concentration of Cadmium via colorimetric assay and Atomic Absorption Spectroscopy(AAS) was employed to quantify the Cadmium in lake water samples before and after treatment with biosorbent. Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscope (SEM) were performed to characterize the surface properties for adsorptive removal of metal ions, and antioxidant studies were conducted to assess the role of S. bryopteris in suppressing oxidative stress.

Global concern revolves around the persistent attributes of harmful non-biodegradable contaminants, especially heavy metals and metalloids, which draws attention to environmental pollution. As regards to soil ecosystem, microorganisms have a significant impact on heavy metal concentrations, either actively or passively. Heavy metal toxicity profoundly impacts the metabolic activities of microbial communities, leading to disruptions in essential cellular processes. Heavy metals interfere with the enzymatic reactions necessary for energy of metabolism, nutrient cycling, and organic matter degradation, resulting in reduced microbial growth and activity. The Biolog Ecoplate method is used as an effective tool for assessing microbial activity. The potential use of Biolog Ecoplate in the study of microbial community structure and diversity in heavy metal-polluted soil was investigated. In order to achieve this goal, multiple keywords combinations were used to filter the most important results in the field. In metal-contaminated soils, the use of Biolog Ecoplate has led to notable changes in microbial community composition, marked by increased populations of resistant and metal-reducing microorganisms.

Abstract The present study investigates the impact of varying concentrations of PVC microplastics (PVC–MPs) – specifically 0 (no PVC–MPs), 2, and 4 mg L− 1 –alongside different arsenic (As) levels of 0 (no As), 150, and 300 mg kg− 1 in the soil, with the concurrent application of copper oxide–nanoparticles (CuO–NPs) at 0 (no CuO –NPs), 25 and 50 µg mL− 1 to barley (Hordeum vulgare L.) plants. This research primarily aims to assess plant growth and biomass, photosynthetic pigments and gas exchange characteristics, oxidative stress indicators, as well as the response of various antioxidants (both enzymatic and non-enzymatic) and their relevant genes expression, proline metabolism, the AsA–GSH cycle, and cellular fractionation within the plants. The findings showed that increased levels of PVC–MPs and As stress in the soil significantly reduced plant growth and biomass, photosynthetic pigments, and gas exchange characteristics. Additionally, PVC–MPs and As stress increased oxidative stress in the roots and shoots, as evidenced by elevated levels of malondialdehyde (MDA), hydrogen peroxide (H2O2), and electrolyte leakage (EL), which in turn stimulated the production of various enzymatic and non-enzymatic antioxidants, gene expression, and sugar content. Furthermore, a notable increase in proline metabolism, the AsA–GSH cycle, and cellular pigmentation was observed. Conversely, the application of CuO–NPs resulted in a substantial improvement in plant growth and biomass, gas exchange characteristics, and the activity of enzymatic and non-enzymatic antioxidants, along with a reduction in oxidative stress. Additionally, CuO–NPs enhanced cellular fractionation while decreasing proline metabolism and the AsA-GSH cycle in H. vulgare plants. These outcomes provide new insights into sustainable agricultural practices and offer significant potential in addressing the critical challenges of heavy metal contamination in agricultural soils.

Abstract\nNOVELTY STATEMENTIn the current study, coal fly ash contaminated soil was collected in and around Mettur Thermal Power Station, Salem district, Tamil Nadu. The metal concentrations present in the coal fly ash soil samples were analyzed and also used for the isolation of bacteria. The isolates were screened for their multi-metal resistance against three heavy metals (Cu, Ag and Pb) and plant growth-promoting traits (siderophore, phosphate solubilization, IAA, cellulase, HCN, and ammonia production). Among the 12 isolates, the WA4 strain revealed promising results for both metal-resistant and plant growth-promoting activity. In the in vitro pot experiment, Spinacia oleracea (Palak), Red amaranth (Red spinach), Capsicum annum (Green chilly) and Solanum melongena (Brinjal) plants were grown in ash-contaminated soil treated with different concentrations of selected bacterial inoculum (25%, 50%, 75% and 100%) along with a control pot. The results of the study indicated that the ash-contaminated soil treated with bacterial inoculum distinctly increased the growth of plants when compared to untreated soil (control). Thus, the best-performing strain WA4 could be utilized as a good bio-stimulant for promoting the growth of selected plants in the re-vegetation programs of ash-contaminated soil.The novelty of the experimental work relies on the phytoremediation of heavy metals in coal fly ash-contaminated soil from Mettur Thermal Power Station, Salem District, Tamil Nadu. A significant prospect for phytoextraction of heavy metals (Cu, Ag and Pb) was seen by utilizing potent bacteria Stutzerimonas stutzeri in association with common food crops (Red amaranth, S. oleracea, C. annum, S. melongena). The plants had optimum protein, sugars, biomass, chlorophyll, flavonoids, and phenolic content implying their effectiveness in heavy metal cleanup. Furthermore, there was an upsurge in CAT and POD enzymes which reduces ROS in plants. The maximum absorption of heavy metals was observed in Red amaranth with Ag (0.38 ± 0.09 mg/kg), Pb (0.20 ± 0.30 mg/kg), and Cu (0.45 ± 0.64 mg/kg) followed by S. oleracea with Ag (0.22 ± 0.16 mg/kg), Pb (0.10 ± 0.44 mg/kg), and Cu (0.24 ± 0.08 mg/kg). [ABSTRACT FROM AUTHOR]

This study investigates the impact of copper (Cu) stress on tomato plants (Solanum pimpinellifolium) and explores the potential of chitosan and nanosilver (nAg) in mitigating its effects. Copper, while essential for plant growth, can be toxic at elevated levels, leading to oxidative stress and reduced plant productivity. This research focuses on determining how chitosan and nAg treatments influence plant growth, fruit yield, and biochemical responses under Cu-induced stress. A greenhouse experiment was conducted, where tomato plants were treated with Cu, chitosan, nAg, and their combinations. The results revealed that chitosan improved root growth, and enhanced antioxidant properties, including increased ascorbic acid and lycopene content. Nanosilver treatments, while reducing shoot growth, significantly increased fruit yield and potassium uptake. The combination of Cu with chitosan or nAg provided synergistic benefits, improving plant resilience and fruit quality. Specifically, copper+chitosan (Cu+Ch) increased dry matter and delayed ripening, while Cu+nAg enhanced potassium uptake and overall fruit yield. Additionally, Cu accelerated the ripening of tomatoes. These findings suggest that chitosan and nanosilver are effective strategies to mitigate copper toxicity in tomato plants, offering a sustainable approach to improve crop productivity and quality under heavy metal stress conditions. [ABSTRACT FROM AUTHOR]

Lead (Pb) is a heavy metal with no clear biological benefit that is toxic to wildlife and humans. Although Pb has been banned from several consumer products, it is not regulated in ammunition for big‐game hunting (e.g., cervids) in New York, USA. Wildlife species that scavenge remains of game harvested with Pb ammunition can be exposed to bullet fragments through ingestion and potentially develop toxicosis. To make evidence‐based decisions for reducing risk from bullet‐derived Pb, we first empirically identified avian and mammalian scavengers of white‐tailed deer (Odocoileus virginianus) remains in New York through an online survey during July‐August 2023, where community members submitted images of scavengers from game cameras. We conducted species vulnerability and utility assessments using published evidence and pre‐existing frameworks. Despite inherent limitations, we documented an extensive array of avian (n = 17) and mammalian (n = 14) scavengers. We estimated bald eagles (Haliaeetus leucocephalus) and golden eagles (Aquila chrysaetos) as most vulnerable to Pb toxicosis, followed collectively by American goshawks (Accipiter atricapillus), American crows (Corvus brachyrhynchos), and common ravens (C. corax). We also determined bald eagles to be best‐suited as bioindicators of bullet‐derived Pb, followed by American goshawks. Red‐tailed hawks (Buteo jamaicensis) and great horned owls (Bubo virginianus) equally ranked third. Integrating vulnerability and utility assessments point to bald eagles as the most vulnerable scavengers to Pb toxicosis and best‐suited bioindicators of bullet‐derived Pb. Because regulation of Pb ammunition for big‐game hunting is an ongoing socio‐political issue, wildlife managers and conservationists can address health risks through monitoring species vulnerable to toxicosis and instituting surveillance programs using the most effective bioindicators. [ABSTRACT FROM AUTHOR]

Global concern revolves around the persistent attributes of harmful non-biodegradable contaminants, especially heavy metals and metalloids, which draws attention to environmental pollution. As regards to soil ecosystem, microorganisms have a significant impact on heavy metal concentrations, either actively or passively. Heavy metal toxicity profoundly impacts the metabolic activities of microbial communities, leading to disruptions in essential cellular processes. Heavy metals interfere with the enzymatic reactions necessary for energy of metabolism, nutrient cycling, and organic matter degradation, resulting in reduced microbial growth and activity. The Biolog Ecoplate method is used as an effective tool for assessing microbial activity. The potential use of Biolog Ecoplate in the study of microbial community structure and diversity in heavy metal -polluted soil was investigated. In order to achieve this goal, multiple keywords combinations were used to filter the most important results in the field. In metal-contaminated soils, the use of Biolog Ecoplate has led to notable changes in microbial community composition, marked by increased populations of resistant and metal -reducing microorganisms. [ABSTRACT FROM AUTHOR]

Spent mushroom substrate (SMS) is a kind of agricultural waste currently used as amendment, however, its remediation efficacy on heavy metal-contaminated soil has not been comprehensively evaluated. In this study, the effects of SMS and its compost (CSMS) on soil environment (including lead availability, physicochemical properties, nutrient content, enzyme activity, bacterial community) and plant growth (including germination, photosynthesis, and biomass) in lead-contaminated soil were investigated. Independent germination test and pot experiments of water spinach were carried out under 600 mg/kg lead contamination and 5% amendment dosage. The results showed that SMS increased the germination rate by 45.1% and CSMS decreased it by 60.9%. Both amendments enhanced the photosynthesis and increased the fresh weight of water spinach by more than 12.6% in polluted soil, but SMS had a negative effect on photosynthesis and decreased the fresh weight in unpolluted soil. The SMS and CSMS reduced soil lead availability and thus decreased the lead content of water spinach by more than 6.1%. SMS increased soil pH, while CSMS decreased it. CSMS increased soil conductivity, organic carbon, and available N more than SMS. Both amendments consistently and positively impacted on soil enzymes and bacteria. In conclusion, composting is beneficial to increase the available N of SMS, which prevents SMS from competing with plants for N during mineralization. However, CSMS should not be directly used in the sowing period, because its alkalinity and high salt content may inhibit seed germination. [ABSTRACT FROM AUTHOR]

The present study investigates the impact of varying concentrations of PVC microplastics (PVC–MPs) – specifically 0 (no PVC–MPs), 2, and 4 mg L− 1 –alongside different arsenic (As) levels of 0 (no As), 150, and 300 mg kg− 1 in the soil, with the concurrent application of copper oxide–nanoparticles (CuO–NPs) at 0 (no CuO –NPs), 25 and 50 µg mL− 1 to barley (Hordeum vulgare L.) plants. This research primarily aims to assess plant growth and biomass, photosynthetic pigments and gas exchange characteristics, oxidative stress indicators, as well as the response of various antioxidants (both enzymatic and non-enzymatic) and their relevant genes expression, proline metabolism, the AsA–GSH cycle, and cellular fractionation within the plants. The findings showed that increased levels of PVC–MPs and As stress in the soil significantly reduced plant growth and biomass, photosynthetic pigments, and gas exchange characteristics. Additionally, PVC–MPs and As stress increased oxidative stress in the roots and shoots, as evidenced by elevated levels of malondialdehyde (MDA), hydrogen peroxide (H2O2), and electrolyte leakage (EL), which in turn stimulated the production of various enzymatic and non-enzymatic antioxidants, gene expression, and sugar content. Furthermore, a notable increase in proline metabolism, the AsA–GSH cycle, and cellular pigmentation was observed. Conversely, the application of CuO–NPs resulted in a substantial improvement in plant growth and biomass, gas exchange characteristics, and the activity of enzymatic and non-enzymatic antioxidants, along with a reduction in oxidative stress. Additionally, CuO–NPs enhanced cellular fractionation while decreasing proline metabolism and the AsA-GSH cycle in H. vulgare plants. These outcomes provide new insights into sustainable agricultural practices and offer significant potential in addressing the critical challenges of heavy metal contamination in agricultural soils. [ABSTRACT FROM AUTHOR]

Simple Summary: In Central Europe, one of the main issues in wildlife management at present is its increasing abundance. As population density increases, diseases that directly or indirectly affect humans are also becoming more prevalent. Although fibropapillomatosis is one of the diseases that does not threaten humans, the accumulation of some heavy metals in tumours has been shown to occur at concentrations that would already be toxic to humans and wildlife. In general, the heavy metal content in wild animal tissues is a partly known topic that was studied on muscle or internal organs but is almost unstudied in tumours. Therefore, we evaluated the content of selected heavy metals in roe deer—the most widespread wildlife species across Europe. If the accumulation of these heavy metals in the tumours also affects the muscle of the individual, which is then intended for consumption by the final consumer, such meat could be considered a health hazard. This pilot study is a cornerstone for further research to clarify the safety or otherwise of meat from wild game affected by fibropapillomatosis. In recent decades, there has been an increase in European wild ungulate populations, often associated with a decline in health and spread of disease. This is true for the roe deer (Capreolus capreolus), the most common European cervid, with populations apparently affected by fibropapillomatosis, an increasingly common cancer. To date, however, there has been little research into this disease, thus many interactions remain unclear and descriptions of tumour composition are poorly validated. The main aim of the present study was to evaluate the presence and concentration of toxic heavy metals in roe deer skin tumours. Our results confirmed the presence of virtually all the metals tested for, i.e., Pb, Hg, Cd, As, Cr, Mn, Al, Co, Cu, Ni, Se, Zn, and Fe, with the highest average concentrations found for Cr (0.99 mg/kg−1 ± 2.23 SD), Cd (0.03 mg/kg−1 ± 0.03 SD), and Hg (0.02 mg/kg−1 ± 0.02 SD), exceeding FAO limits for meat from slaughtered animals. We also observed a significant positive relationship between heavy metal concentration and age, especially for Pb, As, Hg, Mn, Se, Al, Zn, and Ni. Our findings provide a strong baseline for further research on the impact of fibropapillomatosis, not only on the welfare and health status of game but also on the final consumer of venison, which in many respects is regarded as a high-quality, ecological, and renewable wild resource. While deer with this disease are not considered qualitatively or medically defective, they could represent a potential reservoir of substances toxic to humans and could affect substance levels in adjacent tissues or the animal as a whole. [ABSTRACT FROM AUTHOR]

Diverse anthropogenic activities and lack of knowledge on its consequences have promoted serious heavy metal contaminations in different aquatic systems throughout the globe. The non-biodegradable nature of most of these toxic heavy metals has increased the concern on their possible bioaccumulation in aquatic organisms as well as in other vertebrates. Among these aquatic species, fish are most sensitive to such contaminated water that not only decreases their chance of survivability in the nature but also increases the probability of biomagnifications of these heavy metals in higher order food chain. After entering the fish body, heavy metals induce detrimental changes in different vital organs by impairing multiple physiological and biochemical pathways that are essential for the species. Such alterations may include tissue damage, induction of oxidative stress, immune-suppression, endocrine disorders, uncontrolled cell proliferation, DNA damage, and even apoptosis. Although uncountable reports have explored the toxic effects of different heavy metals in diverse fish species, but surprisingly, only a few attempts have been made to ameliorate such toxic effects. Since, oxidative stress seems to be the underlying common factor in such heavy metal–induced toxicity, therefore, a potent and endogenous antioxidant with no side effect may be an appropriate therapeutic solution. Apart from summarizing the toxic effects of two important toxicants, i.e., cadmium and lead in fish, the novelty of the present treatise lies in its arguments in favor of using melatonin, an endogenous free radical scavenger and indirect antioxidant, in ameliorating the toxic effects of heavy metals in any fish species. The protective role of melatonin against lead (Pb) and cadmium (Cd) induced toxicities in fish. After entering the body of any fish, Pb and Cd induce generation of harmful free radicals that induce oxidative stress within the target cell/tissue/organ which in turn modulates the gene expression of different important genes responsible for maintaining the antioxidant defense system and inflammatory pathways, thus causing diverse complications in the physiology of the aquatic organism. Melatonin, on the other hand, defends the cell/tissue (marked as an inhibitory symbol) by scavenging these unwanted free radicals and indirectly modulating the antioxidant system to restore the intracellular oxidative load, thus restricting the propagation of the toxicity cascade (marked as cross symbols) and protecting different organs of the fish from harmful toxic effects triggered by Pb or Cd. [ABSTRACT FROM AUTHOR]

The increasing proximity of the Dudumbia dumpsite, an open dumpsite in Navrongo, Ghana, to human settlements necessitates an investigation of the soil quality to safeguard the environment from heavy metal toxicity. This study examined the impact of waste dumping activities on the physicochemical properties of the soil, as well as the level of heavy metal (Pb, Cd, Ni, Cr, As, Hg, Cu, Mn, and Zn) contamination and associated risks. Various contamination and risk assessment tools were used, including the geoaccumulation index (Igeo), pollution load index (PLI), potential ecological risk (Er), and potential ecological risk index (PERI). The study found significant improvements in notable soil attributes such as phosphorus (P), organic carbon (C), total nitrogen (N), calcium (Ca), magnesium (Mg), potassium (K), sodium (Na), and effective cation exchange capacity, with percentage increases ranging from 50.8 to 2078.3%. Igeo values ranged from 2.07 to 6.20, indicating contamination levels from moderate to extreme. The PLI and PERI values were 16.241 and 1810, respectively. The Er values for the heavy metals ranged from 36 to 607, indicating ecological risk levels from low to very high, with Cd and Hg posing very high risks. These results suggest that while the dumpsite soil shows improvements in some characteristics favourable for plant cultivation, waste dumping significantly contributes to heavy metal contamination. The soil at the dumpsite is deteriorated and poses significant health risks, particularly due to Cd and Hg. Therefore, remediation efforts should prioritise mitigating the risks posed by Cd and Hg. [ABSTRACT FROM AUTHOR]

Several industries such as leather tanning, coal mining, steel and metal processing are responsible for heavy metals contamination in water. Heavy metals contamination in water can have harmful effects on both aquatic and terrestrial animals by entering the food chain. Due to the higher toxicity of heavy metals, it is necessary to remove heavy metal ions from water. There are several physio-chemical methods available, including ion exchange, membrane filtration, chemical oxidation, and electrochemical methods. However, these methods have some disadvantages like expensive and generating harmful byproducts. Biosorption is a cost-effective and eco-friendly method for the removal of heavy metals from contaminated water. Biosorbents are derived from biomasses of plant, bacterial, algal, fungal, agro-waste, etc. The biosorbents have several functional groups on their surface providing them a high binding capacity for heavy metal ions. Mathematical models such as isotherms, thermodynamics, and kinetic studies help explain how heavy metals adsorb on biosorbents. This review provides comprehensive details on the heavy metals heavy metal contaminated in water including the source, toxicity and biosorption of heavy metal ions. This review also provides the mechanism of heavy metal biosorption including mathematical models.

Heavy metal contamination in water and soil presents a growing global issue that poses significant risks to environmental integrity and human well-being. Various heavy metals, including arsenic (As), lead (Pb), mercury (Hg), cadmium (Cd), and chromium (Cr), contaminate ecosystems. These metals enter the environment through both natural processes and human activities such as coal mining, leather production, metal processing, agriculture, and industrial waste disposal. With their high toxicity and tendency to accumulate in organisms, heavy metals induce oxidative stress in cells, resulting in organelle damage. This toxicity can lead to genetic mutations and histone alterations. Given the severe effects of heavy metals, urgent actions are required to eliminate them from polluted soil and water. While physicochemical techniques like membrane filtration, precipitation, oxidation, and reduction exist, they have limitations. Hence, there is a pressing need to devise environmentally friendly and cost-efficient approaches for heavy metal removal. This article examines heavy metal contamination in water and soil, its adverse impacts, and the cleanup of heavy metals using eco-friendly methods.

The heavy metal toxicity of marketed Ayurvedic herbal formulations has been sporadically reported in the literature. Drakshadi (DK) and Gandharvahastadi (GK) decoctions are widely prescribed classical Ayurvedic herbal formulations. The potential adverse heavy metal toxicity due to consequent intake of DK and GK have been published in scientific papers or reported through pharmacovigilance. The objective of our investigation was to determine the presence of heavy metals in marketed DK and GK, with reference to the Ayurveda Pharmacopeia of India (API) standards. In this study, the concentration of four heavy metals, Arsenic (As), Cadmium (Cd), Lead (Pb), and Mercury (Hg) were investigated using Inductively Coupled Plasma-Mass Spectrometer (ICP-MS). These metals are not known to have any role in the pharmacological activity of these formulations. However, their presence beyond acceptable limits can have harmful consequences. Eighteen random samples each of DK and GK decoctions were collected from different pharmacy outlets, Kerala province, India. We tested 36 market samples of the above formulations for heavy metals, which were found to be within the limits prescribed by the Ayurvedic Pharmacopoeia of India. Our study suggests that heavy metal contamination of Ayurvedic formulations may not be widespread as suspected. However, continuous dynamic monitoring of Ayurvedic herbal formulations for heavy metal contamination is warranted considering the possibility of inadvertent contamination of raw drugs from environmental exposure. [ABSTRACT FROM AUTHOR]

Phytoremediation is a budding and efficient in situ green technique hyper accumulators plants are used to remove pollutant elements from soil. The plants are selected on the basis of biomass, accumulation of metals, coefficient of bioaccumulation (BC) and tolerance index (TI) in shoots of crops. Therefore, a pot house experiment was done to compare efficiency of three genotypes of brassica i.e. Brassica juncea, Brassica campestris and Brassica napus for decontamination of nickel (Ni) from Ni spiked sandy loam soils. The soil was contaminated at six Ni levels including 0, 2.5, 5, 10, 20 and 40 mg kg−1 soil. The shoot and grain dry matter yield of different brassica genotypes declined with the increased levels of Ni application. The grain yield ranged between 2.70 to 1.78 g pot−1 with increased levels of Ni application. However, Ni accumulation in grain and shoot of all brassica genotypes augmented with increasing Ni level in soil. The concentration of Ni in brassica genotypes increased from 8.6–58.4% in grains and 8.3–53.6% in shoots over controlThe contamination indices (BC and TI) were also recorded highest in B. juncea and B. napus whereas lowest was seen in B.campestris. All brassica genotypes showed increase in BC from 11.4–14.1, while TI decreased from 92.9–65.8% with increased levels of Ni contamination. Also, the soil analysis recorded the increased concentration of DTPA-Ni in soils of all the brassica genotypes. Thus, among all the studied brassica genotypes, B. juncea proved to be the most promising hyperaccumulator for phytoremediation of Ni spiked soils. [ABSTRACT FROM AUTHOR]

Heavy metals are naturally occurring elements. Their widespread distribution in the environment has raised questions about their possible consequences on both human health and the environment. So, the toxicological and safety assessment of these heavy metals is one of the major issues in recent days. An accurate method for the determination of nickel in bulk drugs was required due to its high toxicity risk. The aim of the current study was to develop a validated analytical technique for the determination of nickel content in bulk drugs using an atomic absorption spectrometer. The wavelength was 232 nm, and the integration duration was 5.0 seconds. It was determined that the detection and quantification limits were 0.051 mg/L and 0.15 mg/L, respectively. The recovery rates for nickel concentrations spiked by 50%, 100%, and 150% in meclizine hydrochloride were determined to be 109.33%, 96.5%, and 97.55%, respectively. The status of heavy metals and trace elements in bulk drugs were discussed in this article, along with an easy-to-use AAS approach that can be applied at the industrial level to ensure the quality and uniformity of bulk medications and other related products. [ABSTRACT FROM AUTHOR]

Heavy metal pollution is a gradually growing environmental issue that hinders the growth and development of plants, and also destabilizes soil. Consequently, eco-friendly phytoremediation methods have gained traction, with energy crops emerging as a particularly effective solution. Energy crops not only provide high-quality plant materials for detoxification and remediation of heavy metal pollution, but also possess energy properties conducive to biofuel production. Therefore, this paper delves into the tolerance mechanism of energy crops towards heavy metal toxicity, elucidating processes such as root complex-mediated inhibition of metal migration and response to reactive oxygen species (ROS) through heavy metal-related proteins, enzyme systems, reactive nitrogen species (RNS), and hormones. Moreover, it summarizes the heavy metals remediation mechanisms of energy crops, including uptake, translocation, chelation, immobilization, and sequestration. This paper explores applications of energy crops in heavy metal pollution remediation, emphasizing the methods for efficient biochar remediation and biofuel generation. Furthermore, potential challenges in using energy crops for heavy metal pollution remediation are outlined. By systematically examining the function mechanisms and prospective applications of energy crops in heavy metal pollution bioremediation, this paper serves as a valuable reference for both research and practical implementation in this field. [ABSTRACT FROM AUTHOR]

AbstractThis study investigates the potential of silicate to alleviate cadmium (Cd) toxicity in Gracilaria edulis, an agarophyte. Under various culture conditions spanning 21 days, alga was grown in control, Silicate (Si) medium, and different Cd concentrations (100, 200, and 300 µM) with or without Si100 µM and the effect was measured by photosynthesis O2 evolution, relative growth rate (RGR), biomass, biochemical compositions such as chlorophyll a, phycobilipigments (phycocyanin, allophycocyanin, and phycoerythrin), carbohydrate, protein, lipid peroxidation and Cd accumulation. Cd, a toxic heavy metal, negatively impacts plant and algal growth and metabolism. In contrast, traditionally considered non-essential, Si has growth-promoting properties under various stress conditions. The present study reveals that Si significantly enhances photosynthesis except for Cd300. In Cd100, the photosynthetic O2 evolution was 0.08 nM s−1, whereas in Cd100 + Si, it increased to 0.09 nM s−1. The Cd300 + Si treatment exhibited a rate of 0.07 nM s−1, but in Cd300, it was 0.05 nM s-1 on the 9th day of culture, and the rate was proportionately high on the 18th day of culture. The RGR and biomass significantly improved, particularly when Cd100 was combined with Si. Alga shows a decrease in the chlorophyll a, phycobilin pigments, carbohydrate, and protein content when grown at Cd300 concentration but significantly increased when combined with Si treatment. Alga showed less carbohydrate content (0.30 ± 0.02) at Cd300 µM exposure, of which was increased by adding Si (Cd300 + Si) to 0.34 ± 0.02 mg g−1 alga fresh wt. Cd uptake by the alga is high at Cd300 but considerably low at Cd100 + Si and Cd200 + Si concentrations. Malondialdehyde (MDA) level indicating lipid peroxidation-induced oxidative damage was significantly reduced in Si-treated Cd concentrations compared to heavy metal treatment alone. This study demonstrates that silicate can potentially mitigate the adverse effects of Cd on G. edulis by creating a favorable environment for its growth. Thus, it exhibits promise in alleviating Cd toxicity in G. edulis. [ABSTRACT FROM AUTHOR]

The current investigation demonstrates that the application of MEL (0, 1, and 2 μmol L−1) mitigates the effects of Cr stress 0 (no Cr), 50 and 100 mg kg−1 on coriander (Coriandrum sativum L.) plants. Results from the present study showed that the increasing levels of Cr concentration in the soil induced a significant decrease in shoot length, root length, shoot fresh weight, root fresh weight, shoot dry weight, root dry weight, chlorophyll-a, chlorophyll-b, total chlorophyll, carotenoid contents, net photosynthesis, transpiration rate and stomatal conductance by 36%, 24%, 17%, 64%, 27%, 23%, 19%, 29%, 36%, 18%, 73%, 83%, and 43% respectively. Results findings also showed that the increasing Cr stress in the soil significantly (p< 0.05) decreases calcium, magnesium, iron, and phosphorus contents by 69%, 51%, 89%, and 109% respectively in the roots and decreased by 164%, 97%, 66%, and 124% respectively in the shoots. However, Cr toxicity boosted the production of reactive oxygen species (ROS) by increasing the contents of oxidative stress indicators. Although activities of various antioxidative enzymes and their specific gene expression and also the nonenzymatic antioxidants initially increased up to a Cr level of 50 μM but decreased gradually with the further increase in the Cr level of 100 μM in the medium, compared to those plants which were grown in the control treatment. Results also revealed that the soluble sugar, reducing sugar, and nonreducing sugar were decreased in plants grown under elevating Cr levels but increased the Cr accumulation in the roots and shoots of C. sativum. Although results also illustrated that the application of MEL also decreased Cr toxicity in C. sativum by increasing antioxidant capacity and their gene expression and thus improved the plant growth, photosynthetic pigments, and decrease oxidative stress in the roots and shoots of C. sativum. [ABSTRACT FROM AUTHOR]

Background: Medicinal plants are the best source for a variety of drugs. In traditional practices, the detoxification method is practiced to reduce toxicity of herbs, because low toxicity is one of the characteristics of phytomedicine which have a positive impact on pharmaceutical drugs. Aim: In the present study scientific validation attempt has been made to reduce toxicity by performing traditional practices called Sodhana/detoxification. In our study anti-microbial, phytochemical, heavy metal content and stability were evaluated for the detoxified seeds. Seeds of Nigella sativa were subjected to various detoxification methods like roasting, lime and calcium chloride treatment then ground to powder and extracted with 90% ethanol. Materials and Methods: The anti-microbial study was performed against multidrug-resistant bacterial strains Escherichia coli, Pseudomonas aeroginosa, Staphylococcus aureus and tested for their antifungal activity against Aspergillus niger, Penicillium crysoginum and Malassezia furfur. Metals present in the extract are analyzed by using plasma-optical emission spectrometry and Mass spectrum analysis was done for compound analysis. Results: Our experimental results reveal that Lime treated ethanol extract shows strong inhibitory activity against all the tested microbes than the unprocessed N. sativa extract except E.coli. Data reveals that the treatment of seeds has no impact on their major phytochemical; however, changes in metal concentration were recorded. The frequency of reduction by descending order was Lime=CaCl2= roasted. Moreover, the Stability of the extract followed by 12-month storage at room temperature showed significant anti-microbial activity like fresh extract. UPLC-MS/MS spectrum reveals that lime treated contained high levels of fatty acids. Conclusion: The present study concludes that, after detoxification, the heavy metal content was found to be decreased. Lime treatment is identified as a better method that successfully reduces the toxic elements and possesses high levels of fatty acids and phytochemicals with potent anti-microbial activity and revealed significant improvement in its anti-microbial potency. [ABSTRACT FROM AUTHOR]

Rapid increase in population and industrialization has not only improved the lifestyle but adversely affected the quality and availability of water leading to ample amount of wastewater generation. The major contribution towards wastewater production is from sewage. Regular monitoring and treatment of sewage water is necessary to conserve and enhance the quality of water. The present study focuses on monitoring of sewage water within the sewage system of a residential university. A total of 16 samples from different manholes were collected for physicochemical and heavy metals analysis and compared with final effluent collected from integrated constructed wetlands (ICWs) to assess its removal efficiency. The mean concentrations of influent and effluent were compared with national environmental quality standards (NEQS) for municipal discharge (pH 6–9, COD 150 mg/L, TSS 200 mg/L and TDS 3500 mg/L) and international agricultural reuse standards (IARS) (pH 6–8, COD <150 mg/L, TSS < 100 mg/L) respectively. Among all physicochemical parameters, influent values for chemical oxygen demand (COD) (169.56–258.36) mg/L exceeded the limit of NEQS for discharge into inland waters, whereas for total suspended solids (TSS) the concentration exceeded for discharge into STP (406 mg/L) and inland waters (202.33 mg/L). However, effluent concentrations for all the parameters were found within the permissible limit set by IARS. The removal efficiency for different parameters such as phosphate- phosphorus (PO43-P), COD, TSS, total dissolved solids (TDS) and total kjeldahl nitrogen (TKN) were 52, 53, 54, 35, and 36%, respectively. Heavy metal concentrations were compared with WHO guidelines among which lead (Pb) in effluent and chromium (Cr) in influent exceeded the limit (Pb 0.01 and Cr 0.05 mg/L). Interpolation results showed that zone 2 was highly contaminated in comparison to zone 1 & 3. Statistical analysis showed that correlation of physicochemical parameters and heavy metals was found significant (p < 0.05). [ABSTRACT FROM AUTHOR]

Contamination-free groundwater is considered a good source of potable water. Even in the twenty-first century, over 90 percent of the population is reliant on groundwater resources for their lives. Groundwater influences the economical state, industrial development, ecological system, and agricultural and global health conditions worldwide. However, different natural and artificial processes are gradually polluting groundwater and drinking water systems throughout the world. Toxic metalloids are one of the major sources that pollute the water system. In this review work, we have collected and analyzed information on metal-resistant bacteria along with their genetic information and remediation mechanisms of twenty different metal ions [arsenic (As), mercury (Hg), lead (Pb), chromium (Cr), iron (Fe), copper (Cu), cadmium (Cd), palladium (Pd), zinc (Zn), cobalt (Co), antimony (Sb), gold (Au), silver (Ag), platinum (Pt), selenium (Se), manganese (Mn), molybdenum (Mo), nickel (Ni), tungsten (W), and uranium (U)]. We have surveyed the scientific information available on bacteria-mediated bioremediation of various metals and presented the data with responsible genes and proteins that contribute to bioremediation, bioaccumulation, and biosorption mechanisms. Knowledge of the genes responsible and self-defense mechanisms of diverse metal-resistance bacteria would help us to engineer processes involving multi-metal-resistant bacteria that may reduce metal toxicity in the environment. [ABSTRACT FROM AUTHOR]

Heavy metal (HM) toxicity is a severe abiotic stress that can cause significant harm to plant development and breeding, posing a challenge to sustainable agriculture. Various factors, including cellular toxicity, oxidative stress, osmotic stress, imbalance in the membrane, and metabolic homeostasis cause negative impacts on plant molecular, physiology and biochemistry. Some heavy metals (HMs) are essential micronutrients that play important roles in various plant processes, while excessive amounts can be harmful and have negative impacts on plant growth, metabolism, physiology, and senescence. Phytotoxicity with HMs and the deposition of reactive oxygen species (ROS) and methylglyoxal (MG), can lead to lipid peroxidation, protein oxidation, enzyme inactivation, DNA damage, and harm to other vital components of plant cells. Generally, HM toxicity as environmental stress led to response of plant with different mechanisms, first, the stimulus to external stress, secondly all signals transduction to plant cell and finally it beginning to find appropriate actions to mitigate the adverse stress in terms of physiological, biochemical, and molecular in the cell to survive plant. The purpose of this review is to better understand how plants respond physiologically and biochemically to abiotic HM stress. [ABSTRACT FROM AUTHOR]

Heavy metal toxicity has recently been described in solid organ transplant recipients. Allograft dysfunction or failure associated with arsenic, cadmium, chromium, cobalt and lead exposure have been reported, largely in renal transplant recipients, but also in small numbers of heart transplant recipients and a few liver and lung recipients. Conclusions: [1] In kidney transplant patients, highest tertile arsenic, cadmium and lead plasma levels were associated with increased allograft loss, compared to lower tertile levels; [2] Deteriorating metal hip prostheses may rarely cause heart failure due to cobalt and chromium cardiac toxicity in heart transplant and non-heart transplant patients, which resolves with prosthesis replacement; [3] Heavy metal testing should be considered in patients with multiple risk factors including occupational and environmental exposure, lower socioeconomic status, and multiple morbidities which could be associated with heavy metal toxicity; [4] Chelation therapy, used successfully in some non-transplant patients with chronic renal failure, has not been used systematically in transplant patients and studies are needed

Heavy metal (HM) toxicity is a severe abiotic stress that can cause significant harm to plant development and breeding, posing a challenge to sustainable agriculture. Various factors, including cellular toxicity, oxidative stress, osmotic stress, imbalance in the membrane, and metabolic homeostasis cause negative impacts on plant molecular, physiology and biochemistry. Some heavy metals (HMs) are essential micronutrients that play important roles in various plant processes, while excessive amounts can be harmful and have negative impacts on plant growth, metabolism, physiology, and senescence. Phytotoxicity with HMs and the deposition of reactive oxygen species (ROS) and methylglyoxal (MG), can lead to lipid peroxidation, protein oxidation, enzyme inactivation, DNA damage, and harm to other vital components of plant cells. Generally, HM toxicity as environmental stress led to response of plant with different mechanisms, first, the stimulus to external stress, secondly all signals transduction to plant cell and finally it beginning to find appropriate actions to mitigate the adverse stress in terms of physiological, biochemical, and molecular in the cell to survive plant. The purpose of this review is to better understand how plants respond physiologically and biochemically to abiotic HM stress.

Heavy metal accumulation in agriculture land is one of the major agriculture challenges affecting the crop production and threatens the food safety. A comparative analysis was conducted to assess the tolerance of three sugarcane (Saccharum officinarum L.) genotypes to Lead nitrate under controlled in vitro conditions. Various parameters including fresh and dry weight, callus morphology, shoot morphology, protein contents, catalase, superoxide dismutase, peroxidase, ascorbic acid contents, relative growth rate, stress tolerance index, Pb contents, and Bio concentration factor were evaluated across a range of six different concentrations of Pb (0, 0.1, 0.2, 0.3, 0.4, 0.5, 1 mM). Lead had a noticeable impact on callus growth and regeneration across all three genotypes, whereas it did not significantly affect root regeneration. All genotypes significantly vary at each treatment and parameter except Bio-concentration factor and protein contents. Among the genotypes studied, YT-53 exhibited the highest resistance to Pb-induced stress, followed by CP-77400, while NSG-59 demonstrated the least resistance to Pb stress. Most resistant genotypes can be used in heavy metal effected area for better yield and phytoremediation in Pb affected soil and in other breeding programs.

Moringa oleifera Linn. (MO) or malunggay is a staple food in the province of Cebu, Philippines. Lead detection in green Moringa is important to safeguard public health by identifying and mitigating the risk of lead contamination, which - when consumed - can cause serious health issues, particularly in vulnerable populations such as children and pregnant women. Moringa leaves were collected from the nine cities of Cebu province -namely, Bogo, Carcar, Cebu, Danao, Lapu-Lapu, Mandaue, Naga, Talisay, and Toledo. In each city, three barangays were identified as sampling sites based on their abundance along the roads. The leaves were washed, air-dried, digested, and were then analyzed in triplicate for lead (Pb) content using atomic absorption spectrophotometry. Percent recovery and standard reference materials (SRM) samples were also performed in triplicate. Results revealed that lead levels present in Moringa leaves samples from 27 barangays had Pb content well above the 2 mg kg-1 and only four barangays out of 27 gave a result higher than the 85 mg kg-1 standard set by the World Health Organization for plants and soil, respectively. Total lead concentration in leaf samples from the different sampling sites ranges from 0.52-19.9 mg kg-1, whereas the lead concentration in soil samples varies from 12.5-3086 mg kg-1. Lead concentrations in leaves exhibit a significant seasonal variation (P = 0.0175), but it did not show any significant correlation with respect to Pb levels in the root zone soil (R = 0.279, P = 0.159), which was consistent with the values obtained in the enrichment factor (EF > 1) of lead in leaves. This implied that the lead in the Moringa leaves was not accumulated from the root zone soil but through direct foliar transfer. Also, Moringa along the roadside and industrial zones are no longer safe for consumption, especially in urban and industrial cities. [ABSTRACT FROM AUTHOR]

In today's time, agricultural productivity is severely affected by climate change and increasing pollution. Hence, several biotechnological approaches, including genetic and non-genetic strategies, have been developed and adapted to increase agricultural productivity. One of them is nano-priming, i.e., seed priming with nanomaterials. Thus far, nano-priming methods have been successfully used to mount desired physiological responses and productivity attributes in crops. In this review, the literature about the utility of nano-priming methods for increasing seed vigor, germination, photosynthetic output, biomass, early growth, and crop yield has been summarized. Moreover, the available knowledge about the use of nano-priming methods in modulating plant antioxidant defenses and hormonal networks, inducing salinity tolerance and disease resistance, as well as alleviating heavy metal toxicity in plants, is reviewed. The significance of nano-priming methods in the context of phytotoxicity and environmental safety has also been discussed. For future perspectives, knowledge gaps in the present literature are highlighted, and the need for optimization and validation of nano-priming methods and their plant physiological outcomes, from lab to field, is emphasized. [ABSTRACT FROM AUTHOR]

This study investigates the protective effects of components (Thymol; Thy, Carvacrol; Car, Linalool; Lin, and a-Pinene; AP) and essential oil of Origanum onites L. (O. onites-EO), against lead nitrate-induced cytotoxicity and genotoxicity in Allium cepa L. (A. cepa) root tip cells. These components obtained from O. onites were characterized by gas chromatography (GC). A. cepa bulbs were exposed to 6.25-12.5 mg/L concentrations of the O. onites-EO/components of O. onites-EO for analyses of induction of cytogenetic damage. Then, these bulbs were exposed to 10 mg/L concentrations of lead nitrate for analyses of the protective effects of O. onites and its components. Mitotic abnormalities were evaluated for genotoxicity, and mitotic index (MI) for cytotoxicity. As a result of this study, lead nitrate increased the total chromosomal abnormality amount in A. cepa, indicating genotoxicity. MI was decreased with lead nitrate. However, this effect was significantly improved by components of O. onites-EO. This effect was shown with the decrease in the number of chromosomal abnormalities and increase in MI rates in lead nitrate-induced root cells after exposure to the components of O. onites-EO. The protective effect of O. onites-EO components against the damage caused by lead nitrate in cells can be listed as a-Pinene > Thymol > Carvacrol > Linalool. Among all essential oil components tested, a-Pinene was determined to have the strongest protective effect. Furthermore, the protective effect of the essential oil, which contains all the components, could not be determined. It has been observed that the components of essential oil have different effects, and it can be said that these components suppress the effects of each other in the mixture where they are found together. In conclusion, this study shows that the components of O. onites-EO have a protective effect on lead nitrate-induced A. cepa root cells. [ABSTRACT FROM AUTHOR]

Heavy metal contamination in water and soil presents a growing global issue that poses significant risks to environmental integrity and human well-being. Various heavy metals, including arsenic (As), lead (Pb), mercury (Hg), cadmium (Cd), and chromium (Cr), contaminate ecosystems. These metals enter the environment through both natural processes and human activities such as coal mining, leather production, metal processing, agriculture, and industrial waste disposal. With their high toxicity and tendency to accumulate in organisms, heavy metals induce oxidative stress in cells, resulting in organelle damage. This toxicity can lead to genetic mutations and histone alterations. Given the severe effects of heavy metals, urgent actions are required to eliminate them from polluted soil and water. While physicochemical techniques like membrane filtration, precipitation, oxidation, and reduction exist, they have limitations. Hence, there is a pressing need to devise environmentally friendly and cost-efficient approaches for heavy metal removal. This article examines heavy metal contamination in water and soil, its adverse impacts, and the cleanup of heavy metals using eco-friendly methods. [ABSTRACT FROM AUTHOR]

Several industries such as leather tanning, coal mining, steel and metal processing are responsible for heavy metals contamination in water. Heavy metals contamination in water can have harmful effects on both aquatic and terrestrial animals by entering the food chain. Due to the higher toxicity of heavy metals, it is necessary to remove heavy metal ions from water. There are several physio-chemical methods available, including ion exchange, membrane filtration, chemical oxidation, and electrochemical methods. However, these methods have some disadvantages like expensive and generating harmful byproducts. Biosorption is a cost-effective and eco-friendly method for the removal of heavy metals from contaminated water. Biosorbents are derived from biomasses of plant, bacterial, algal, fungal, agro-waste, etc. The biosorbents have several functional groups on their surface providing them a high binding capacity for heavy metal ions. Mathematical models such as isotherms, thermodynamics, and kinetic studies help explain how heavy metals adsorb on biosorbents. This review provides comprehensive details on the heavy metals heavy metal contaminated in water including the source, toxicity and biosorption of heavy metal ions. This review also provides the mechanism of heavy metal biosorption including mathematical models. [ABSTRACT FROM AUTHOR]

Heavy metals are often found in soil and can contaminate drinking water, posing a serious threat to human health. Molecular pathways and curation therapies for mitigating heavy metal toxicity have been studied for a long time. Recent studies on oxidative stress and aging have shown that the molecular foundation of cellular damage caused by heavy metals, namely, apoptosis, endoplasmic reticulum stress, and mitochondrial stress, share the same pathways as those involved in cellular senescence and aging. In recent aging studies, many types of heavy metal exposures have been used in both cellular and animal aging models. Chelation therapy is a traditional treatment for heavy metal toxicity. However, recently, various antioxidants have been found to be effective in treating heavy metal-induced damage, shifting the research focus to investigating the interplay between antioxidants and heavy metals. In this review, we introduce the molecular basis of heavy metal-induced cellular damage and its relationship with aging, summarize its clinical implications, and discuss antioxidants and other agents with protective effects against heavy metal damage. [ABSTRACT FROM AUTHOR]

• Due to streamlined industrialization, soil contamination has become major cause of scaling down of the crop productivity. • Lead (Pb) toxicity impaired growth, biochemical and yield attributes of Daucus carota L. plants. • Antioxidant enzymes were elevated in D. carota plants in response to Pb stress. • Bio-inoculants improved growth, biochemical and yield contributing factors of D. carota plants grown in Pb contaminated soil. • Bio-inoculants can be potentially used as heavy metal stress ameliorants. Due to streamlined industrialization, soil contamination has become major cause of scaling down of the crop productivity. In the course of current study, the negative effects of lead (Pb) contaminated soil on growth, physiology, antioxidative enzymes and yield of selected genotypes of carrot (Daucus carota L.) were studied. The conclusions drawn from the conducted research depicts that all growth contributing factors were divulges to be decreased under the influence of standardized treatment of lead (Pb). Pb toxicity also reduced yield contributing factors of carrots i.e. root length, diameter and weight. Bio-inoculants improved yield of carrots not only in control but also under Pb stressed conditions. Total soluble sugars and reducing sugars were also reduced by Pb toxicity; while bio-inoculants treatment tends to lower the negative effects of Pb toxicity. The level of enzymes phenylalanine ammonia lyase, polyphenol oxidase and peroxidase increased significantly in response to Pb toxicity. Bio-inoculants reduced the accumulation of these enzymes hence indicating amelioration of Pb toxicity. Application of bio-inoculants played a pivotal role to ameliorate lead (Pb) toxicity, thus, can be potentially used to eradicate Pb stress in contaminated sites. The selected 29 genotypes are categorized into three groups, highly tolerant, moderately tolerant and susceptible. [ABSTRACT FROM AUTHOR]

In the present study, in order to improve the growth performance of hairy vetch (Vicia villosa Roth., Local landrace from Ardabil, Iran) seedlings grown in the soil contaminated with heavy metals Pb and Zn, our attention was directed toward the application of biochar, inoculation with conidial suspension of Trichoderma harzianum Rifai—T22 and management of phosphorus (P) nutrition. Heavy metal toxicity reduced leaf greenness, membrane stability index, maximum quantum yield of PSΙΙ (Fv/Fm), P concentration and uptake in plant tissues and root and shoot biomass, but increased Pb and Zn concentration and uptake in root and leaf, H2O2 and malondialdehyde content and CAT and POX activity in the leaves. The application of biochar, inoculation with Trichoderma fungus and P supplementation increased the shoot P content, which might contribute to the alleviation of P insufficiency and a subsequent elevation in P transfer to aboveground biomass, and eliminated the toxicity of heavy metal on hairy vetch plants, which was revealed in reducing oxidative stress and enhancing plant growth performance. The biochar considerably increased Zn immobilization, while being able to slightly stabilize Pb. Co-application of Trichoderma and 22 mg P/kg soil (22P) increased the concentration and uptake of Zn in the roots and decreased the translocation of this element to the shoots, especially when biochar was not amended. Although the biochar and P inputs could compensate the negative Trichoderma effects, the results suggested that biochar application in combination with fungal inoculation and 22-P supplementation could not only increase hairy vetch growth performance but also decline heavy metal uptake to ensure the production of a forage crop in soils polluted with heavy metals based on the nutritional standards of livestock. [ABSTRACT FROM AUTHOR]